The present invention relates generally to fastening devices, and more particularly to a clip for attaching vines, branches, shoots and the like to a training wire or other support member.
The use of structures in agriculture to support plant growth is a well established practice which has applications in many types of horticulture. Certain types of plants, especially when immature, may bear fruit whose weight can break branches which are not sufficiently supported. This is true of apple trees, as well as stone fruit trees of various sorts. Grapes and tomato plants are other examples of plants which are commonly supported during some stage of their growth.
In American vineyards, grape vines are usually trained to grow on tensioned wires or trellises which are supported by vertical stakes. By training the vines, the plant is encouraged to grow according to an ordered plan which can allow more efficient use of land area. By encouraging the plants to grow on these wires, the fruit is removed from contact with the ground where it may be more susceptible to disease or rot. Harvesting is also facilitated by spreading out the plant growth in a vertical plane thus reducing clumps and tangles which may impede access to fruit.
Produce from farms that grow these types of fruits amounts to billions of dollars yearly, and literally millions of plants are raised in this manner. In order to farm these plant varieties efficiently, several factors must be considered. To grow plants using trellises and wire supports, an efficient method of attaching each plant to its support is needed. Each of these millions of plants which are grown worldwide each year must typically be attached at multiple points, thus the number of attachment devices can be very large indeed. The time required for manipulating these many devices can be quite extensive. Additionally, there may be some skill involved in attaching the plant securely, but without damaging the stalks. Thus, any device which attaches more easily and quickly can result in a major savings of time, money and effort. The ideal device would be simple to use, durable, inexpensive, and would not constrain plant growth.
Conventional attachment devices all suffer from some defect. For centuries, vines have been tied onto stakes using string or twine. This has the disadvantage that the string easily degrades under exposure to sun and rain, and takes time to tie individually.
A very common device which is often used is a xe2x80x9ctwist-tiexe2x80x9d or a piece of wire which is wrapped around the vine and the support. Wire however may rust or degrade when exposed to the elements. It also may require some skill in judging how tightly to apply it. Additionally, bare wire may cut into the plant stalk, either initially when applied, or later when wind causes the plant to whip against its constraints. Also, the wire may constrict the plant as it increases in size, either jeopardizing that portion of the plant, or requiring the wires to be re-tied, an operation which may be more time-consuming than the initial installation. Use of wire ties may also require monitoring of the plants to ensure that constriction is not occurring, which again may be costly in time and labor.
There have been several attempts to improve upon conventional twist-ties. U.S. Pat. No. 3,800,365 to Bruggert discloses a clip for attaching stalks to wire. These appear to be limited to attaching vertical stalks to horizontal supports or vice versa. The clips appear spindly and may take some time to attach correctly. They would easily become entangled with each other in a bag, and one can imagine that a good deal of effort would be required to disentangle a batch which contains one or two hundred of these Bruggert clips.
U.S. Pat. No. 4,099,299, also to Bruggert et al., appears to be a version of the same kind of clip, but allows horizontal to horizontal attachment, or vertical to vertical. This invention also suffers from many of these same defects as the earlier version, specifically entanglement problems and attachment difficulties.
Thus there is a great need for an improved fastening clip for attaching plant vines and stalks to support wires or trellises.
Accordingly, it is an object of the present invention to provide an attachment device which is very quick and easy to apply.
Another object of the invention is to provide an attachment device which holds the plants firmly.
And, another object of the invention is to provide an attachment device which is durable, and can be reused for multiple growing seasons.
Yet another object of the present invention is to provide an attachment device which expands to accommodate plant growth without constricting the plant.
Still another object of the present invention is to provide an attachment device which is inexpensive to manufacture.
A further object of the present invention is to provide an attachment device which requires no skill to apply.
A still further object of the present invention is to provide an attachment device which does not chafe or abrade the vine or stalk of the plant.
Briefly, one preferred embodiment of the present invention is a resilient fastening clip for attaching a plant member to a portion of a support structure, such as a wire. The clip includes a clip wall that creates a first enclosure and a second enclosure which are integrally fashioned from the clip wall. The first enclosure has a first enclosure entry mouth, which may be resiliently spread open to allow entrance of a support structure portion, and which closes after insertion to prevent outward passage of the support structure portion. The second enclosure has a second enclosure entry mouth which may be resiliently spread open to allow entrance of a plant member, and which closes after insertion to prevent outward passage of said plant member. The first enclosure entry mouth may be configured to lie either within the second enclosure, or may be external to it. A flexible arm is optionally provided to help capture the support wire. The clip may also have a number of gripper protrusions which prevent rotation of the plant member within the second enclosure.
An alternative embodiment of a resilient clip has a transverse wire channel formed in the first enclosure region, into which a support wire may be inserted. This wire channel may have retaining barbs to prevent lateral movement of the clip upon the support wire. The clip may also have an enlarged retaining arm which divides the second closure into inner and outer enclosure portions. A plant stem is introduced into the inner portion of the second enclosure, and is held in place between the retaining arm and the inner surface of the clip wall. As the plant stem increases in diameter, the retaining arm is forced to pivot further and further into the outer enclosure portion. The arm may be configured with a thinner portion near the top of the pivot point, which allows the arm to twist and rise out of the plane of the clip. The tip of the arm thus can rise above the height of the clip wall and continue to rotate. This allows the plant to grow unrestricted into the full area of the second enclosure. Even after the plant""s diameter has grown to fill the second enclosure area, further growth is still not restricted. The clip is able to flex, and the second enclosure can enlarge even further to accommodate the plant""s growth.
Another embodiment of a resilient clip has an enlarged first enclosure that is configured to accept a trellis slat. The clip may have a key with a retaining notch that helps to confine the trellis slat within the first enclosure.
An advantage of the present invention is that it can be easily applied to both the support and the plant member, thus saving much time and money over the multiple instances which are required in a field of plants.
Another advantage of the invention is that the clip holds the plant member firmly.
And, another advantage is that the invention is constructed of rugged plastic or other durable weather resistant material which makes it reusable over the course of many seasons.
Still another advantage of the present invention is that the clip is resilient and can expand as the plant grows and develops, so that the clip does not have to be replaced as the plant increases in size. This eliminates the costs involved in replacement, and in monitoring for necessity of replacement.
A further advantage is that the clip is simple and inexpensive to manufacture using standard molding or extrusion techniques.
Yet another advantage of the present invention is that the clips are very easy to apply and require very little skill to fasten correctly.
An additional advantage of the present invention is that the walls of the clip are relatively wide compared to the gage of wires, and thus tend to abrade the stalks and vines of the plants less. The clips may be configured with retaining barbs which help to hold the plant member more securely, without damaging it.
A still further advantage of the present invention is that they are less easily entangled than some prior art inventions.
These and other objects and advantages of the present invention will become clear to those skilled in the art in view of the description of the best presently known mode of carrying out the invention and the industrial applicability of the preferred embodiment as described herein and as illustrated in the several figures of the drawings.